Talk: Evolution of Disease Burden Over 5 Years in a Multicentre Inception SLE Cohort (2009 ACR/ARHP Annual Scientific Meeting)

Tuesday, October 20, 2009: 3:30 PM

108 B (Pennsylvania Convention Center)

Murray B. Urowitz¹, Dafna D. Gladman¹, Dominique Ibañez¹ and Systemic Lupus International Collaborating Clinics (SLICC)², ¹University of Toronto, Toronto Western Hospital, Toronto, ON, ²Toronto, ON

Presentation Number: 1932

Purpose: The evolution on an annual basis of disease activity and damage and the annual accrual of key autoantibodies in patients with SLE is unknown. We describe the annual occurrence of these features in an inception cohort of patients with SLE. Method: An international research network comprising 27 centres from 11 countries has followed an inception cohort of SLE patients yearly according to a standardized protocol between 2000 and 2009. Of these, 298 patients followed for a minimum of 5 years constitute the study population. Clinical disease activity was assessed using SLEDAI-2K and disease damage using the SLICC/ACR Damage Index (SLICC/DI). ANA, Anti-DNA and anticardiolipin, antibody levels and the presence of the lupus anticoagulant were assessed at each visit. Descriptive statistics were used. Results: Of the 298 patients followed for at least 5 years, 86.6% were female, 55.4% were Caucasian, 12.1% were Black, 14.4% were Asian, 16.1% Hispanic and 2.0% other. 41.9% were married and 60.4% had at least College education. Their mean age at enrolment was 35.3 years and SLEDAI-2K at enrolment was 5.9. The duration from diagnosis to enrolment was 5.5 months.
FU
SLEDAI-2K
SLICC/DI
n
Mean ± std
n
Mean ± std
0
298
5.93 ± 5.54
143*
0.37 ± 0.80
1
268
3.67 ± 4.11
237
0.55 ± 0.94
2
271
3.71 ± 4.50
270
0.67 ± 1.09
3
265
3.51 ± 3.64
262
0.79 ± 1.16
4
272
3.30 ± 4.05
269
0.94 ± 1.28
5
298
3.37 ± 4.15
295
1.01 ± 1.35
* SLICC/DI performed only in those with > 6 months disease duration.
FU
N
ANA
Anti-DNA
ACL
LA
0
298
93.6
29.3
25.6
26.9
1
268
95.3
37.6
21.8
26.7
2
271
95.3
48.3
17.3
24.2
3
265
96.3
50.7
20.2
29.1
4
272
96.3
53.4
23.7
34.2
5
298
97.0
55.4
25.6
32.6
Mean SLEDAI-2K decreases to low levels in the first year and then remains low. SLEDAI-2K was significantly lower at each year in Caucasians compared to the combined “other” ethnicities.
Mean SLICC/DI increases progressively over the 5 years but there was no significant difference at each year between Caucasians and “others”. Although ANA positivity is high at enrolment, the percent positivity increases by almost 4% over 5 years. Frequency of anti-DNA positivity is lower at enrolment but increases over 5 years. Anticardiolipin antibody does not increase over 5 years but the lupus anticoagulant increases slightly.

Conclusion: As expected disease activity in newly diagnosed patients decreases over their first 5 years but disease damage increases. However key antibody levels ran variable courses over this period. For example ANA positivity increases only slightly over 5 years. Similarly anti-DNA antibody positivity was low in the first year of disease but rose to 55% by 5 years. Anticardiolipin antibody and the lupus anticoagulant were more constant over the first 5 years of disease.

Keywords: systemic lupus erythematosus (SLE)

Disclosure: M. B. Urowitz, None; D. D. Gladman, None; D. Ibañez, None.

1932 - Evolution of Disease Burden Over 5 Years in a Multicentre Inception SLE Cohort